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| United States Patent |
5,730,624
|
|
Lester
, et al.
|
March 24, 1998
|
Secondary contact lock arrangement
Abstract
A secondary lock is provided to prevent deflection of a tine and therefore
prevent loss of a contact, which can be used in miniature connectors
having a large number of contacts and corresponding miniature tines. A
first tine (71, FIG. 6 ) at each contact-receiving passage (20) of the
connector, has a substantially straight inner tine side (82) extending
forwardly and with a radially inward directional component, and has an
outer tine side (84) with a forward surface portion (86 A) that extends
substantially parallel to the axis of the passage. The secondary lock
includes a post (24) that is slidable parallel to the contact-receiving
passage and that has a blocking surface (90) that lies close to, but
slightly spaced from the forward surface portion of the outer tine side.
The forward surface portion (86A) extends forwardly about as far as
contact-abutting ends (64, 65) of the tines. The contact-receiving
passages are arranged in two concentric circles (21, 23 FIG. 4), with a
post-receiving hole (30A) engaging tines at passages lying at each circle.
Each post has long ribs (14, FIG. 12 ) to lightly hold the secondary lock
in place during shipment, and has short ribs (142) to secure the secondary
lock in place after the contacts are installed.
| Inventors:
|
Lester; Lester Joaquin (Signal Hill, CA);
Van Trump; Gary Neil (Santa Ana, CA)
|
| Assignee:
|
ITT Corporation (New York, NY)
|
| Appl. No.:
|
565515 |
| Filed:
|
November 30, 1995 |
| Current U.S. Class: |
439/595 |
| Intern'l Class: |
H01R 013/40 |
| Field of Search: |
439/595,752,587
|
References Cited
U.S. Patent Documents
| 3838382 | Sep., 1974 | Sugar | 439/595.
|
| 3937545 | Feb., 1976 | Cairns et al.
| |
| 3971613 | Jul., 1976 | Kobler.
| |
| 4544220 | Oct., 1985 | Afello et al.
| |
| 4557542 | Dec., 1985 | Coller et al.
| |
| 4565416 | Jan., 1986 | Rudy et al.
| |
| 4602837 | Jul., 1986 | Sian et al.
| |
| 4698030 | Oct., 1987 | Ryll et al. | 439/752.
|
| 4714437 | Dec., 1987 | Dyki | 439/595.
|
| 4749372 | Jun., 1988 | Betsui | 439/587.
|
| 4749373 | Jun., 1988 | Brekosky et al. | 439/595.
|
| 4776813 | Oct., 1988 | Wilson et al. | 439/587.
|
| 4826452 | May., 1989 | Sian et al. | 439/595.
|
| 4902247 | Feb., 1990 | Suzuki et al. | 439/595.
|
| 4936798 | Jun., 1990 | Hass et al. | 439/752.
|
| 4944695 | Jul., 1990 | Tsuji et al. | 439/595.
|
| 4963106 | Oct., 1990 | Wendling et al. | 439/595.
|
| 4973268 | Nov., 1990 | Smith et al. | 439/595.
|
| 5071369 | Dec., 1991 | Denlinger et al. | 439/595.
|
| 5135416 | Aug., 1992 | Hass et al. | 439/752.
|
| 5273443 | Dec., 1993 | Frantz et al. | 439/595.
|
| 5496194 | Mar., 1996 | Huss, Jr. | 439/595.
|
Primary Examiner: Bradley; P. Austin
Assistant Examiner: Wittels; Daniel
Attorney, Agent or Firm: Freilich Hornbaker Rosen
Claims
What is claimed is:
1. A connector which has an insulator with a plurality of contact-receiving
passages having substantially parallel passage axes extending in forward
and rearward directions, a plurality of electrical contacts that are each
slidable in said forward direction into one of said passages and that each
has a shoulder part forming a shoulder that faces largely in said rearward
direction, said connector including tines that each has an abutting part
that lies in an abutting position in line with the shoulder of one of said
contacts to prevent rearward movement of a fully installed contact but
with the tine abutting part being deflectable to allow the shoulder part
to pass rearwardly of the tine, and a secondary lock that is installable
in said insulator after a first of said contacts is installed in a first
of said passages, said secondary lock having a first post that blocks
deflection of a first of said tines to prevent its abutting part from
moving out of said abutting position, characterized by:
said first tine has radially inner and outer tine sides;
said post is slidable substantially parallel to a first axis of said first
passage and said post has a blocking part that lies adjacent to but
substantially out of contact with said outer tine side to not deflect said
first tine but to only limit radially outward movement of said first tine.
2. The connector described in claim 1 wherein:
said first tine has a thin bendable rear portion, and said first tine has a
radially thicker front portion with a maximum radial thickness at least
twice the thickness of said thin rear portion.
3. The connector described in claim 1 wherein:
said first tine radially outer side extends forwardly substantially no
further than said abutting part.
4. The connector described in claim 1 wherein:
said outer tine side has a forward portion that extends substantially
parallel to said first passage axis.
5. The connector described in claim 1 wherein:
said plurality of contact-receiving passages are arranged in at least two
concentric passage circles and said passages form a plurality of groups of
three passages that are equally distant from a group axis that extends
parallel to said passage axis;
said insulator has a plurality of separate post-receiving holes that each
extends along one of said group axes, with each post having a blocking
part lying adjacent to a tine at each passage of a group of three
passages.
6. The connector described in claim 5 wherein:
said secondary lock includes a largely plate-like holder and a plurality of
posts, including said first post, mounted on said holder;
said holder extending substantially in a holder circle that is concentric
with said passage circles, and said holder has a central hole to avoid
blocking areas immediately in front of at least some of said
contact-receiving passages.
7. The connector described in claim 5 wherein:
said insulator has a front end with a recess that closely receives said
plate-like holder.
8. The connector described in claim 6 wherein:
said holder has a periphery with a plurality of cutouts therein to avoid
blocking areas immediately in front of said passages.
9. The connector described in claim 1 wherein:
said insulator has a post-receiving hole with hole walls that are
substantially cylindrical, and said post has a cylindrical portion that
fits closely in said hole and has a pair of ribs at largely opposite sides
of the post that are formed to have an interference fit with the walls of
the hole, with a first of said ribs being longer than the second of said
ribs.
10. A connector for holding a plurality of contacts that each has a
rearwardly-facing shoulder, comprising:
an insulator which has a plurality of contact-receiving passages with
parallel passage axes that extend in forward and rearward directions for
receiving contacts, a plurality of resilient tines around each of said
passages with said tines each extending generally forwardly and with a
radially inward directional component toward a corresponding passage axis,
with said contacts each being installable into one of said passages by
insertion of the contact in a forward direction therein until a plurality
of tines around the passage snap to a position immediately behind said
shoulder;
said contact receiving passages are arranged in a plurality of concentric
circles including an inner circle and an outer circle, and at least some
of said passages are arranged in a plurality of groups that each includes
at least three passages clustered around a group axes, including two
passages lying on said outer circle and one passage lying on said inner
circle, and said insulator has a post-receiving hole extending along each
of said group axes; and
a secondary lock which includes a holder and a plurality of posts extending
rearwardly from said holder, each post having three blocking parts with
each blocking part lying adjacent to a tine of a different passage of a
group of passages to prevent the tine from deflecting away from a position
directly rearward of the shoulder of a corresponding contact.
11. The connector described in claim 10 wherein:
said tines are formed with a first tine of each plurality of tines that lie
around a passage, having a thin and bendable rear portion and a thicker
front portion with an outer surface, each of said contacts has a rear part
lying immediately rearward of the contact shoulder with said first tine
pressing radially inwardly against said contact rear part, and said
blocking parts of said posts extend substantially parallel to said passage
axis and lie slightly radially spaced from the radially outer surface of
the first line at each passage of the set when the first tine presses
radially inwardly against a contact rear part.
12. The connector described in claim 10 wherein:
each of said posts has a rear end of cylindrical shape.
13. The connector described in claim 10 wherein:
said connector has an axis and said holder has a hole with hole walls
extending around said connector axis.
14. A connector for holding a plurality of contacts that each have a
rearwardly-facing shoulder, comprising:
an insulator which has a plurality of contact-receiving passages with
parallel passage axes that extend in forward and rearward directions for
receiving contacts, a plurality of resilient tines around each of said
passages with said tines each extending generally forwardly and with a
radially inward directional component toward a corresponding passage axis,
with said contacts being installable into one of said passages by
insertion of the contact in a forward direction therein until a plurality
of tines around the passage snap to a position immediately behind said
shoulder;
said insulator has a post-receiving hole lying adjacent to a first of said
passages and extending rearwardly from a front end of said insulator;
a secondary lock which includes a post having a blocking part adjacent to a
first tine that lies around said first passage, to limit deflection of
said first tine away from the axis of said first passage;
said post having a largely cylindrical portion that fits closely in said
post-receiving hole, and having a pair of ribs that are formed to have an
interference fit with the walls of the hole, with a first of said ribs
extending further rearward than the second of said ribs wherein when the
second of said ribs lies in said hole the interference fit is larger.
15. The connector described in claim 14 wherein:
said ribs are positioned so when said first rib lies in said post-receiving
hole, but a rear end of said second rib lies at said front end of said
insulator, said post blocking part does not lie sufficiently rearward to
limit deflection of said first tine, but when said second rib lies
substantially fully in said hole said post blocking part limits deflection
of said first tine.
Description
BACKGROUND OF THE INVENTION
Electrical contacts are commonly retained in contact-receiving passages of
a connector insulator by resilient tines. A connector is pushed forwardly
into a connector-receiving passage, and radially outwardly deflects tines
lying around that passage when a shoulder on the contact passes the tines.
The tines then snap to a position behind the shoulder, thereby preventing
rearward removal of the contact. A secondary lock can be provided to
prevent at least one tine at each contact-receiving passage, from
deflecting radially outwardly. This prevents inadvertent contact rearward
movement, as during mating of the connector with another one. Where a
large number of contacts must be retained in a connector of small size, it
can be difficult to provide a secondary lock for a tine at each contact
passage. A secondary lock which could be constructed at relatively low
cost, which provided reliable secondary locking of a tine, and which could
be readily used to hold a tine at each of many contact-receiving passages,
would be of value.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention, a connector is
provided with a secondary lock of relatively simple and reliable
construction. The connector has contact-receiving passages that may be
arranged in concentric circles, and has tines that surround the passages.
Each tine has a free abutting end that lies in line with a contact
shoulder to prevent withdrawal of an installed contact. A first tine at
each contact-receiving passage, has a radially outer tine side with a
forward portion that extends about as far forward as the tine abutting
ends. The forward portion outerside preferably extends substantially
parallel to the passage axis. The secondary lock includes a post that is
slidable substantially parallel to the passage axis and that has a
blocking part lying adjacent to but slightly spaced from the outer side of
the first tine. The post prevents the first tine from deflecting radially
outwardly sufficiently to allow removal of the contact.
The secondary lock includes a largely plate-like holder and a plurality of
cylindrical posts that each projects into a corresponding post-receiving
hole in the connector insulator. Each post has a pair of ribs, including a
longer rib which first enters a post-receiving hole, and a shorter rib.
The posts are first partially installed, with each longer rib lying in a
post-receiving hole in a moderate interference fit therewith that keeps
the secondary lock in place during transport to a customer. A customer
inserts the electrical contacts, and then pushes the secondary lock firmly
into place, thereby also inserting the shorter ribs into the
post-receiving holes to provide a larger interference fit of each post in
a hole.
The novel features of the invention are set forth with particularity in the
appended claims. The invention will be best understood from the following
description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded isometric view of a connector system constructed in
accordance with the present invention, and showing the rear end of the
plug connector.
FIG. 2 is an exploded front isometric view of the plug connector of FIG. 1,
with the secondary lock not yet installed.
FIG. 3 is a sectional view of the connector of FIG. 2, shown prior to
installation of the electrical contacts in the secondary lock.
FIG. 4 is a front elevation view of the connector of FIG. 3.
FIG. 5 is a rear elevation view of the connector of FIG. 3.
FIG. 6 is a partial sectional view taken on line 6--6 of FIG. 4, but with
the electrical contacts and secondary lock in fully installed positions.
FIG. 7 is an enlarged view of a portion of the connector of FIG. 6, with
the tines shown at positions assumed prior to contact installation.
FIG. 8 is a view taken on line 8--8 of FIG. 3.
FIG. 9 is a side elevation view of the secondary lock of FIG. 2.
FIG. 10 is a front elevation view of the secondary lock of FIG. 9.
FIG. 11 is a rear elevation view of the secondary lock of FIG. 9.
FIG. 12 is a view of a portion of the connector of FIG. 6, with the
secondary lock at an intermediate position.
FIG. 12A is a sectional view taken on line 12A--12A of FIG. 12, with the
secondary lock in his fully installed position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a connector system 10 which includes a receptacle
connector 12 mounted on a wall 13 such as the transmission casing of a
vehicle, and a plug connector 14 which can be mated to the receptacle
connector by moving the plug connector in a forward direction F. The
figure also shows an electrical contact 16 which is crimped to the front
end of an insulated wire 18, the contact being installable in
contact-receiving passages 20 of the plug connector 14. The passages are
arranged along two concentric circles 21, 23 that are concentric with the
axis 130 of the plug connector.
FIG. 2 shows the front and sides of the plug connector 14, and shows a
secondary lock 22 that can be moved in a rearward direction R into the
connector. As the secondary lock moves rearwardly, posts 24 held by a
plate-like holder 26 can enter post-receiving holes 30 of the connector.
The particular connector shown has twelve contact-receiving passages 20,
with four spaced along the inner circle 21 and with eight spaced along the
outer circle 23. The secondary lock has four posts 24, with each post
being associated with three of the passages 20, including one on the inner
circle and two on the outer circle, to lock three corresponding contacts
in the passages.
FIG. 3 shows the overall construction of the connector, prior to
installation of the contacts and the secondary lock, but with some fluid
seals not shown. The connector includes an insulator 40 that has front and
rear insulator members 42, 44 that are each preferably constructed of an
engineering plastic (a Young's Modulus of Elasticity of at least 50K psi).
A grommet 46 of soft rubber or other elastomeric material lies behind the
rear insulator member. The insulator forms the contact-receiving passages
20 that are each designed to receive an electrical contact by inserting
the contact in a forward direction F along the axis 52 of the passage.
Each insulator member has a passage portion 50, 51 that forms part of each
passage 20. The connector includes a set 54 of tines at each passage, to
prevent rearward removal of an installed contact. For the particular
connector shown, the tines 54 are molded as part of the rear insulator
member 44, although it is possible to form the tines on a separate member.
The connector includes stakes (not shown) that hold the front and rear
insulator members together.
FIG. 6 is a view taken on line 6--6 of FIG. 4, showing a socket electrical
connector 16 in a fully installed position in a contact-receiving passage
20, and also showing the secondary lock 22 in its fully installed
position. The contact has a shoulder part or flange 60 with a
rearwardly-facing shoulder 62 that lies immediately forward (a small
distance forward) of abutting ends 64 of the tines 54. The contact has a
rear portion 66 that is crimped to the wire 18, with the wire extending
rearwardly through a passage portion 68 in the grommet 46.
As indicated in FIG. 8, each set 54 of tines includes four tines 71-74. The
first tine 71 is different from the other three tines 72-74. As shown in
FIG. 7, the second tine 72 (and the tines 73, 74) has radially inner and
outer tine sides 76, 78, with the radial direction being with respect to
the passage axis 52. The radially inner and outer sides 76, 78 are both
substantially straight and extend with forward F and radially inward I
(towards the axis 52) directional components from a mounted rear end 80 of
the tine, to the free, or abutting end 64 of the tine. The abutting end 64
lies close to the contact retention shoulder 62 and in line with it (in a
direction parallel to axis 52) to prevent the shoulder from moving
rearwardly by more than a small amount (a small amount is permissible when
connectors mate).
The first tine 71 of the set has a radially inner tine side 82 of the same
shape and orientation as the inner sides of the other tines. However, the
first tine 71 has a radially outer surface 84 with a surface forward
portion 86 that extends substantially parallel to the passage axis 52. A
corresponding secondary lock post 24 has a blocking part 90 that lies
close to the outer surface portion 86 to limit radially outward deflection
of the first tine by an amount that would cause the first tine abutting
end 64A to move out of line with (i.e. axially rearward of) the contact
shoulder 62.
When the contact 16 is installed, it deflects the tines, so in the fully
installed position of the contact the front outer surface portion 86 of
the first tine is slightly deflected to the position 86A. The blocking
portion 90 of the post is still spaced a distance A from the first tine,
but prevents a much further radially outward deflection of the first tine.
The distance A is provided so the post can be slid rearwardly to the final
position, without damaging the first tine 71. It is possible for a post
blocking portion 90 to lightly engage the tine surface at 86A, but because
of manufacturing tolerances a slight gap A of an average of more than one
thousandth inch is usually provided.
FIG. 6 shows the set of tines 54 with the contact fully installed, and with
the first tine forward outer surface 86A slightly spaced from the locking
portion 90 of the post 24. It may be noted that prior to insertion of the
post 24 and during forward installation of the contact 16, the tines will
be radially outward deflected by a considerable amount, with the first
tine being deflected so its forward radially outer surface is deflected to
the position 86B. Resilience of the tines causes them to move radially
inwardly after the shoulder has passed, and they are intended to bear
against the rear portion 66 of the contact.
The post 24 is of substantially cylindrical shape, at least at a rear
portion 92, or at least the blocking portions 90 extend substantially
parallel to the axis 94 of the post-receiving hole 30. As a result, the
amount of first tine deflection allowed by the post is determined only by
the diameter of its rear portion, rather than by the depth of rearward
movement of the post during its installation. The radially outer surface
86A of the first tine is preferably constructed so it extends
substantially parallel to the passage axis 52 in the fully installed
position of the contacts, which makes accurate manufacture easier.
As shown in FIG. 7, the first tine has a thin bendable rear portion 100
where most of the tine bending occurs, and the tine forward portion 102 is
of increased thickness. The forward portion 102 has a maximum radial
thickness that is preferably at least twice as great as the rear portion
100. It is possible to provide only a thick rib portion at the tine
forward portion 102, although applicant prefers to thicken the entire
width of the forward portion. It also would be possible to provide a bump
of small axial length instead of the axially extending surface 86, but it
would be more difficult to maintain the tolerance of such a bump. The
other tines such as 72 are preferably of constant thickness along their
lengths.
The front end 64A of the first tine is shown as extends substantially no
further forward than the abutting surfaces 64, 64A of the tines; the outer
surface 86 of the first tine preferably extends no further forward than
the front 104 of the contact flange 60. This helps control the radial
position of the first tine outer surface 86. The contact flange 60 has a
length about equal to the diameter of the contact immediately behind the
shoulder 62.
FIG. 4 shows the twelve contact-receiving passages 20 arranged in groups of
three each, around each of four post-receiving holes 30A -30D. Three
contact-receiving passages 20A-20C and corresponding sets of tines, are
arranged symmetrically about a group axis 94 and about each post-receiving
hole 30A which extends along the axis 94. One passage 20A lies on the
inner circle 21 and two passages 20B, 20C lie on the outer circle 23. As
shown in FIG. 8, the first tine 71, 71 B, 71C of each set lies adjacent to
a post-receiving hole 30A, and therefore to the post lying therein. This
allows the post 24 to provide a secondary lock for the first tine of each
of three contact-receiving passages 20A-20C. The fact that the rearward
end of each post 24 is substantially cylindrical, permits easy manufacture
of the posts and installation of the posts without regard as to which post
is received in which post-receiving hole.
FIG. 2 shows that the secondary lock 22 includes four posts 24 that extend
rearwardly from the plate-like holder 26. The holder 26 has a central hole
110 with scallop-shaped cutouts 112, and has a periphery 114 with similar
scallop-shaped cutouts 116. The cutouts 112 at the walls of the central
hole 110 avoid blocking the contact-receiving passages 20 and the contacts
therein, while the cutouts 116 at the outer periphery of the holder serve
the same purpose. The insulator 40 has a recess 120 in its front face that
receives the plate-like holder 26, so the forward face 122 of the holder
lies substantially flush with the front 124 of the insulator where the
front 126 of the contact-receiving passages lie. The front 126 of the
passages forming lead-in guides for pins that engage the sockets of the
contacts. The holder 26 and posts 24 are symmetrically arranged about an
axis which is coincident with the axis 130 of the connector. As a result,
it does not matter as to which of the posts 24 are received in which of
the post-receiving holes 30.
FIG. 9 shows that although each post 24 is of substantially cylindrical
shape, each post is provided with a long rib 140 and a short rib 142.
Applicant commonly manufactures all of a connector except for contacts,
and ships them to a customer who installs the contacts. In order to reduce
the number of loose parts and avoid confusion on the part of the customer
as to the orientation at which the secondary lock must be installed (it
doesn't matter but the customer may not remember this), applicant prefers
to partially install the secondary lock to an intermediate position.
FIG. 12 shows the secondary lock 22 in its intermediate position. Most of
each post 24 is of cylindrical shape, with a diameter B that is
substantially the same or only slightly smaller than the diameter C of the
hole in which it fits, so the rear portion 92 of the post is accurately
positioned with respect to the walls of the post-receiving hole 30 near
its rear end. When the long rib 140 lies in the cylindrical post-receiving
hole 30, it results in a moderate interference fit, which assures that the
secondary lock will not fall out or be accidentally removed. When the
short rib 142 also lies in the post-receiving hole 30, this results in a
large interference fit, which assures that the secondary lock will not be
removed unless a tool is applied to force it out so that a contact can be
removed. Applicant prefers to initially install the secondary lock 22 so
the long rib 140 lies in the hole 30, but the front end 144 of the short
rib lie at the front end 30F of the hole 30. This can be easily
accomplished by pushing the secondary lock 22 rearwardly with a moderate
force. When the customer receives the connector with the secondary lock in
its intermediate position, the customer installs the contact and then
forces the secondary lock 22 to its fully installed position, wherein the
post reaches the position shown in phantom lines in FIG. 12.
When the secondary lock 22 is pushed rearwardly to its fully installed
position, a high resistance to such full installation indicates that one
of the contacts has not been fully installed. That is, the resistance
indicates that one of the first tines is at the position shown in FIG. 6
at 86B wherein it blocks the post.
A connector of the illustrated construction that applicant has designed has
an overall length A (FIG. 3) of 1.05 inch and other dimensions
proportional to those illustrated. Each post has a diameter B (FIG. 12) of
0.140 inch (.+-.0.002 inch) while each post-receiving hole has a diameter
C of about 0.142 inch, so the rearward portion of each post is closely
controlled in radial position by the walls of the post-receiving hole.
Each rib 140, 144 has a radial height D of 0.009 inch, so that when only
the long rib 140 lies in a post-receiving hole, there is an interference
of about 0.007 inch, while when both posts 140, 142 lie in a hole there is
an interference fit of about 0.016 inch. The ribs each have a relatively
small width E (FIG. 9) such as 0.020 inch.
Thus, the invention provides a connector and a secondary lock for
preventing contact-locking tines from releasing a contact of the
connector, where the connector can be constructed of small size despite
having many contacts and the secondary lock can be easily constructed and
installed and reliably locks a tins in place at each contact. A first tins
lying beside a contact-receiving passage, has a radially thick forward
portion. The secondary lock includes a post that can slide into a
post-receiving hole in the connector, so a blocking part of the post
extends substantially parallel to the contact-receiving passage. The
blocking part of the post preferably lies slightly spaced from the
radially outer side of the first tine. This avoids requiring the post to
deflect the tine, but instead allows the post to only lie beside the tine
and prevent excess tine deflection. The post preferably has a plurality of
blocking portions such as three of them, which each lies beside a first
tine of a different contact-receiving passage. The rear portion of the
post is preferably cylindrical so it can be constructed at low cost and
accurately guided by a simple cylindrical post-receiving hole, to a
position where each blocking part of the post lies adjacent to a first
tine of a different contact-receiving passage. The secondary lock
preferably includes a plurality of posts with forward ends held by a
plate-like holder that has a central hole and that has cutouts in its
periphery and preferably also in its central hole, to avoid blocking areas
immediately in front of the contact-receiving passages. The outer surface
of each post is preferably substantially cylindrical, but with long and
short ribs. The long rib providing a moderate interference fit to hold the
secondary lock during shipment to a customer, and the long and short ribs
together forming a large interference fit to hold the posts in their fully
inserted positions.
Although particular embodiments of the invention have been described and
illustrated herein, it is recognized that modifications and variations may
readily occur to those skilled in the art, and consequently, it is
intended that the claims be interpreted to cover such modifications and
equivalents.
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